/**
 * Copyright (c) 2016 Tino Reichardt
 * All rights reserved.
 *
 * This source code is licensed under both the BSD-style license (found in the
 * LICENSE file in the root directory of this source tree) and the GPLv2 (found
 * in the COPYING file in the root directory of this source tree).
 *
 * You can contact the author at:
 * - zstdmt source repository: https://github.com/mcmilk/zstdmt
 */

#ifndef THREADING_H_938743
#define THREADING_H_938743

#include "debug.h"

#if defined(__cplusplus)
extern "C" {
#endif

#if defined(ZSTD_MULTITHREAD) && defined(_WIN32)

/**
 * Windows minimalist Pthread Wrapper, based on :
 * http://www.cse.wustl.edu/~schmidt/win32-cv-1.html
 */
#ifdef WINVER
#undef WINVER
#endif
#define WINVER 0x0600

#ifdef _WIN32_WINNT
#undef _WIN32_WINNT
#endif
#define _WIN32_WINNT 0x0600

#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif

#undef ERROR /* reported already defined on VS 2015 (Rich Geldreich) */
#include <windows.h>
#undef ERROR
#define ERROR(name) ZSTD_ERROR(name)

/* mutex */
#define ZSTD_pthread_mutex_t CRITICAL_SECTION
#define ZSTD_pthread_mutex_init(a, b) ((void)(b), InitializeCriticalSection((a)), 0)
#define ZSTD_pthread_mutex_destroy(a) DeleteCriticalSection((a))
#define ZSTD_pthread_mutex_lock(a) EnterCriticalSection((a))
#define ZSTD_pthread_mutex_unlock(a) LeaveCriticalSection((a))

/* condition variable */
#define ZSTD_pthread_cond_t CONDITION_VARIABLE
#define ZSTD_pthread_cond_init(a, b) ((void)(b), InitializeConditionVariable((a)), 0)
#define ZSTD_pthread_cond_destroy(a) ((void)(a))
#define ZSTD_pthread_cond_wait(a, b) SleepConditionVariableCS((a), (b), INFINITE)
#define ZSTD_pthread_cond_signal(a) WakeConditionVariable((a))
#define ZSTD_pthread_cond_broadcast(a) WakeAllConditionVariable((a))

/* ZSTD_pthread_create() and ZSTD_pthread_join() */
typedef struct {
    HANDLE handle;
    void* (*start_routine)(void*);
    void* arg;
} ZSTD_pthread_t;

int ZSTD_pthread_create(ZSTD_pthread_t* thread, const void* unused, void* (*start_routine)(void*), void* arg);

int ZSTD_pthread_join(ZSTD_pthread_t thread, void** value_ptr);

/**
 * add here more wrappers as required
 */

#elif defined(ZSTD_MULTITHREAD) /* posix assumed ; need a better detection method */
/* ===   POSIX Systems   === */
#include <pthread.h>

#if DEBUGLEVEL < 1

#define ZSTD_pthread_mutex_t pthread_mutex_t
#define ZSTD_pthread_mutex_init(a, b) pthread_mutex_init((a), (b))
#define ZSTD_pthread_mutex_destroy(a) pthread_mutex_destroy((a))
#define ZSTD_pthread_mutex_lock(a) pthread_mutex_lock((a))
#define ZSTD_pthread_mutex_unlock(a) pthread_mutex_unlock((a))

#define ZSTD_pthread_cond_t pthread_cond_t
#define ZSTD_pthread_cond_init(a, b) pthread_cond_init((a), (b))
#define ZSTD_pthread_cond_destroy(a) pthread_cond_destroy((a))
#define ZSTD_pthread_cond_wait(a, b) pthread_cond_wait((a), (b))
#define ZSTD_pthread_cond_signal(a) pthread_cond_signal((a))
#define ZSTD_pthread_cond_broadcast(a) pthread_cond_broadcast((a))

#define ZSTD_pthread_t pthread_t
#define ZSTD_pthread_create(a, b, c, d) pthread_create((a), (b), (c), (d))
#define ZSTD_pthread_join(a, b) pthread_join((a), (b))

#else /* DEBUGLEVEL >= 1 */

/* Debug implementation of threading.
 * In this implementation we use pointers for mutexes and condition variables.
 * This way, if we forget to init/destroy them the program will crash or ASAN
 * will report leaks.
 */

#define ZSTD_pthread_mutex_t pthread_mutex_t*
int ZSTD_pthread_mutex_init(ZSTD_pthread_mutex_t* mutex, pthread_mutexattr_t const* attr);
int ZSTD_pthread_mutex_destroy(ZSTD_pthread_mutex_t* mutex);
#define ZSTD_pthread_mutex_lock(a) pthread_mutex_lock(*(a))
#define ZSTD_pthread_mutex_unlock(a) pthread_mutex_unlock(*(a))

#define ZSTD_pthread_cond_t pthread_cond_t*
int ZSTD_pthread_cond_init(ZSTD_pthread_cond_t* cond, pthread_condattr_t const* attr);
int ZSTD_pthread_cond_destroy(ZSTD_pthread_cond_t* cond);
#define ZSTD_pthread_cond_wait(a, b) pthread_cond_wait(*(a), *(b))
#define ZSTD_pthread_cond_signal(a) pthread_cond_signal(*(a))
#define ZSTD_pthread_cond_broadcast(a) pthread_cond_broadcast(*(a))

#define ZSTD_pthread_t pthread_t
#define ZSTD_pthread_create(a, b, c, d) pthread_create((a), (b), (c), (d))
#define ZSTD_pthread_join(a, b) pthread_join((a), (b))

#endif

#else /* ZSTD_MULTITHREAD not defined */
/* No multithreading support */

typedef int ZSTD_pthread_mutex_t;
#define ZSTD_pthread_mutex_init(a, b) ((void)(a), (void)(b), 0)
#define ZSTD_pthread_mutex_destroy(a) ((void)(a))
#define ZSTD_pthread_mutex_lock(a) ((void)(a))
#define ZSTD_pthread_mutex_unlock(a) ((void)(a))

typedef int ZSTD_pthread_cond_t;
#define ZSTD_pthread_cond_init(a, b) ((void)(a), (void)(b), 0)
#define ZSTD_pthread_cond_destroy(a) ((void)(a))
#define ZSTD_pthread_cond_wait(a, b) ((void)(a), (void)(b))
#define ZSTD_pthread_cond_signal(a) ((void)(a))
#define ZSTD_pthread_cond_broadcast(a) ((void)(a))

/* do not use ZSTD_pthread_t */

#endif /* ZSTD_MULTITHREAD */

#if defined(__cplusplus)
}
#endif

#endif /* THREADING_H_938743 */
